Does Android support MIDI?
MIDI (Musical Instrument Digital Interface) is a technical standard that describes a communications protocol, digital interface, and electrical connectors that connect a wide variety of electronic musical instruments, computers, and related audio devices for playing, editing and recording music. Midi Definition & Meaning – Merriam-Webster
Some common applications of MIDI include: controlling synthesizers, sound modules, samplers, drum machines, live performance sequencing, computer music sequencing, and more. MIDI allows different instruments to communicate with each other by transmitting realtime performance data and commands such as note-ons, note-offs, program changes, controller data, and more. This allows MIDI devices to be connected together with a simple cable, which enables them to be synchronized and layered in various ways.
MIDI Support in Early Android Versions
Prior to Android 3.0 Honeycomb, released in 2011, the Android operating system did not include native support for MIDI (according to this discussion). MIDI (Musical Instrument Digital Interface) is a technical standard that allows electronic musical instruments, computers, and other equipment to connect and communicate with each other. Without native MIDI support, Android devices were not able to easily connect to MIDI devices or work with MIDI data before Android 3.0.
Some early third-party Android apps implemented their own MIDI communication by interfacing directly with the audio hardware. However, without OS-level support, MIDI functionality was limited. There was no standard Android MIDI API available for developers to integrate MIDI into their apps in a simple, consistent way.
Overall, MIDI support in early Android releases was extremely limited. MIDI connectivity and capabilities relied on app developers building custom solutions. This made MIDI integration fragmented across different apps and difficult for most developers to implement.
Native MIDI Support Added in Android 3.0
A major advancement for MIDI on Android came with the release of Android 3.0 Honeycomb in 2011. This version introduced native support for MIDI devices and APIs (https://source.android.com/docs/core/audio/midi).
The Android 3.0 MIDI APIs allow apps to enumerate connected MIDI devices, send and receive MIDI messages, and manage MIDI sessions. This enabled much more seamless integration of external MIDI controllers, keyboards, and other gear with Android devices.
Whereas earlier Android versions required workaround solutions for MIDI, the native APIs standardized and simplified MIDI implementation. Any app using the MIDI APIs could connect to compatible MIDI hardware without needing custom integration.
Android 3.0 unlocked professional grade MIDI abilities on Android. This allowed music creation apps to flourish with improved workflow and responsiveness. The APIs paved the way for Android to become a serious platform for musicians and audio professionals.
Using the Android MIDI API
The Android MIDI API allows apps to send and receive MIDI data over USB or virtual MIDI ports. It was introduced in Android 3.0 (Honeycomb) and provides low-latency audio input/output and MIDI capabilities. The API is based on the OpenSL ES framework and allows devices running Android 3.0 or higher to function as MIDI controllers, synthesizers, sequencers and more.
To use the MIDI API, developers need to add the android.media.midi package to their projects. The API includes classes like MidiDevice, MidiReceiver, MidiSender and MidiConnection. Apps can use MidiManager to obtain MidiDevice instances, open input and output ports, and establish connections between devices. The API provides callback methods to receive and send MIDI events in real-time.
Some key capabilities of the Android MIDI API include:
- Enumerating connected MIDI devices
- Opening input and output ports on devices
- Sending and receiving MIDI messages
- Creating virtual MIDI ports for inter-app communication
- Obtaining timing information from MIDI events
Overall, the API provides a full-featured interface for MIDI on Android. Developers can leverage it to build creative music apps and tools.
Example MIDI Applications
One popular MIDI application for Android is Caustic 3, a modular synthesizer and music creation tool. Caustic allows you to build synthesizers, effects chains, and songs via a drag-and-drop interface. With Android’s MIDI support, Caustic can connect to external MIDI keyboards and controllers to play instruments and manipulate parameters in real-time. Caustic offers high-quality synth engines, a piano-roll editor, live performance modes, and support for exporting tracks. While focused on electronic music production, Caustic’s flexibility makes it useful for musicians of all backgrounds. Other examples include MidiFlow, which turns your device into a MIDI controller for other gear and software, and MIDISuite which provides MIDI file playback and sequencing capabilities. The availability of MIDI on Android has enabled the porting and growth of productive musical tools.
Connecting MIDI Devices
Many MIDI keyboards, controllers, and other devices can connect to Android devices via USB. This allows you to use the MIDI device to control synthesizer and digital audio workstation apps running on your Android. Here’s how to connect a MIDI device:
First, you’ll need a USB host adapter or cable to connect the MIDI device to your Android. Many newer Android devices support USB OTG which allows them to act as a USB host. For older devices without built-in USB host support, you can use a USB OTG adapter cable or hub.
Once you have the proper adapter or cable, connect your MIDI device to your Android using a standard USB cable. Make sure to follow the directions for your specific MIDI device for proper operation. You may need to put the MIDI device into a special MIDI over USB mode using its menus and controls.
After physically connecting the MIDI device, you may need to enable MIDI support in your Android settings. Go to Settings > Developer options and enable the MIDI option. This allows your Android device to recognize the MIDI device.
Finally, open your synthesizer or DAW app and it should automatically detect the connected MIDI device allowing you to start using it to play and record MIDI notes and controller messages. Apps like Caustic, FL Studio Mobile, or others with MIDI support should work.
With the proper cables and adapter, connecting most MIDI devices to an Android device is straightforward. Just be sure to enable MIDI support in your settings to allow communication between the hardware and your music apps.
Latency Considerations
One challenge that Android MIDI developers face is latency. Latency refers to the delay between when a MIDI note is played on a controller and when the sound is heard from the device. On Android, this latency can often be higher than on other platforms like iOS.
There are a few reasons why Android struggles with lower latency MIDI playback:
- The Android audio system was not originally designed with professional low latency audio in mind.
- Extra buffering and processing in the system adds small delays.
- Differences between various Android devices and system versions make consistency tricky.
That said, latency has improved significantly on Android over the years. For example, the addition of the Android MIDI API in 3.0 helped standardize low latency MIDI support across devices. Furthermore, Android’s audio pipeline has become more streamlined. Many pro audio apps can now achieve roundtrip latency under 40ms on modern flagship Android devices.
There are also techniques Android MIDI developers can use to work around latency issues. For example, adding a pre-delay on MIDI note events to match the expected latency. Overall, while latency can still be a challenge, Android has made great strides to become far more capable for professional MIDI applications.
Tips for Android MIDI Developers
Android provides a robust MIDI API that makes developing MIDI apps straightforward, but there are some best practices to follow. According to the Developing MIDI applications on Android article, here are some tips:
Use the touch screen for MIDI input. The touch screen can act as an XY pad using the MotionEvent class to generate MIDI control change messages. This allows for expressive interaction.
Leverage the accelerometer for MIDI input. The accelerometer can be used to generate pitch bend information as the device moves. This allows for dynamic gestural control.
Optimize for low latency. Use small buffer sizes and a higher priority thread for MIDI to minimize latency. This results in more responsive MIDI performance.
Support common MIDI interfaces like USB-MIDI or Bluetooth-MIDI for connectivity. Most MIDI keyboards and controllers connect via USB or Bluetooth.
Follow best practices for audio development on Android. Using features like audio engines, low latency audio, and ProAudio can improve MIDI timing and audio integration.
By following these tips, Android MIDI developers can create intuitive, responsive, and professional MIDI applications. The versatile Android MIDI API combined with some optimization provides a powerful platform for MIDI app creativity.
The Future of Android MIDI
Android’s native MIDI support is still relatively new, having been introduced in 2011 with Android 3.0 Honeycomb. As such, there are likely to be continued improvements and enhancements in upcoming Android versions.
One area of focus will likely be reducing latency and improving timing accuracy, which are common challenges with MIDI on Android. Future versions of Android may implement audio engine enhancements to deliver MIDI with lower latency and tighter timing.
Additional MIDI features like support for MPE (Multi-dimensional Polyphonic Expression) may be added to allow for more expressive and nuanced MIDI performances. The Android MIDI API could also be expanded with new capabilities to simplify development of MIDI apps.
As adoption of Android continues to grow globally, we may see more MIDI manufacturers develop Android-compatible devices and peripherals. This could make Android a more appealing platform for music creation.
While native MIDI support on Android has come a long way, there are likely even more enhancements on the horizon that will continue to improve the MIDI experience for Android users and app developers.
Conclusion
In summary, Android has come a long way in supporting MIDI since its initial releases. While early versions of Android did not have native MIDI support, this changed with the release of Android 3.0 Honeycomb which introduced the Android MIDI API. This allows developers to send and receive MIDI data using C/C++ code for their Android apps.
The Native MIDI API provides capabilities like enumerating connected MIDI devices, sending and receiving MIDI messages, and getting timing information for precise synchronization. However, there are still some limitations like MIDI latency which developers need to account for.
Overall, Android’s MIDI support has greatly improved over the years and continues to evolve. The platform offers full-featured MIDI capabilities that allow developers to create robust music apps and tools. As the API matures and Android develops, we can expect MIDI on Android to become even more powerful and seamless.
